I am looking for early WRPGs that are interesting from the standpoint of offering varied character builds and/or interesting ways to develop your characters.

Here are some requirements:
* No isomentric games. Isometric games (like Baludr's Gate) are too modern for what I'm looking for.
* No games with continuous movement, certainly not 3d movement. Movement should be grid-based or tile-based. Otherwise, the game is too modern.
* No 3d games with free camera movement. Actually, no 3d games unless they're grid-based like the early Wizardry games.
* If the game was originally released on optical media, it's likely too new. If the game was originally released as a digital download, it's *definitely* too new (though such a game *might* be acceptable if it's stylistically similar to older games, provided that a DRM-free version exists).
* No AD&D-based games, please. I find that the system isn't that great in terms of build variety (until 3e) or character growth.

So, any suggestions? I've found Wizard's Crown and Demon's Winter, and I've played Wasteland and Dragon Wars (not to mention Centauri Alliance), but does anyone have any other ideas?

Hmm. the old good wizardry series (1-5) would be completely applied to your conditions but certainly, you've played them a lot.
How about The Dark Heart of Uukrul? It seems to be applied too.
Also, Legends of Amberland is an excellent Might and Magic 3 clone. Both are available on GOG.

How about Darklands? While it doesn't have turn based combat, but real-time with pause, it is very old-school and has a very complex character development.

And of course the Realms of Arkania games. Turn-based, tile-based, very complex and varied character creation and development.

That's some pretty hefty criteria. If not for some of them, I would have had a couple suggestions like the Pillars of Eternity games (which has my favorite RPG character creation to date) or maybe The Outer Worlds due to its use of buffs and debuffs in character creation.

Betrayal at Krondor? Train through use and by reading books, and a books don't get used up after reading once, can keep rereading and gaining benefits but with ever diminishing returns, and reading takes time, which also means food. And there's also the mental link between mages in the late game, to learn spells, which again takes time.

Hard to tell, what you see as "interesting", but maybe the "Phantasie" series?

https://crpgbook.files.wordpress.com/2022/06/crpg-book-expanded-edition_3.3.pdf (Page 82/Phantasie I)

instead of asking here in hopes that someone here played some sort of random ancient no name super obscure game, why not just go to the crpg addict's blog and read his opinions on games since he's trying to go through as many as possible in chronological order.

http://crpgaddict.blogspot.com/